Ii. gaskets, tubing, connections, sample valves – Labconco FreeZone 2.5 Liter Freeze Dry Systems 76705 Series User Manual
Page 37
Chapter 7: Troubleshooting
Product Service 816-333-8811 or 1-800-522-7658
33
4.
Isolate the pump by disconnecting the vacuum hose from the Freeze Dryer.
Deadhead the pump by inserting the vacuum sensor from a secondary
vacuum gauge into the end of the vacuum hose and observe the vacuum
reading obtained. Confirm that the pump is capable of achieving an
ultimate vacuum less than 0.010 mBar or approximately 10 microns. If an
inadequate vacuum reading is obtained, the pump has most likely failed
and may need to be replaced or rebuilt.
II. Gaskets, Tubing, Connections, Sample Valves
1.
Check all sample valves on the drying chamber/manifold and ensure all
valves are closed or in the vent position. Check to ensure all fittings are
tight and sealed properly against the chamber. Inspect valves for cracks or
cuts.
2.
Inspect gasket(s) for cracks or defects. Ensure the gasket is clean. Apply a
thin coat of vacuum grease to the gasket. Keep in mind too much vacuum
grease can actually cause leaks.
3.
Check the drain line and ensure the drain plug is installed and the tube
appears to be in good condition.
4.
Check all rubber vacuum tubing for signs of deterioration or cracking.
5.
Check all connections and make sure they are secure and leak tight.
6.
When checking the sample valves, pull as much vacuum as possible. If a
vacuum indication is displayed, wiggle or rotate the valves and watch the
gauge for any fluctuations. Fluctuations can indicate a potential vacuum
leak. If the valve seems to be in good condition, remove the valve and
apply a thin coat of vacuum grease to the stem and the outside sealing
surface of the valve body, and reinstall the valve. DO NOT APPLY
VACUUM GREASE TO THE SAMPLE VALVE GASKETS, WHICH
SEAL TO THE WALL OF THE DRYING CHAMBER. If the valve
still seems to be the source of the problem, remove the valve and stopper
the hole with a rubber stopper. Continue checking the other valves.
7.
Make sure that the sample valve bulkhead nuts are tight. Either tighten by
hand or use the wrench supplied with chambers. To use the wrench, first
remove the knob and stem assembly and also the valve body. The pins on
the wrench fit into the round holes of the nut. The nut should be snug but
avoid over tightening. Replace the valve body and knob and stem
assembly.